US president meets with Israeli prime minister and Palestinian president in one-on-one White House meetings.

Barack Obama, the US president, has met with the Israeli and Palestinian leaders to launch a series of meetings aimed at restarting direct talks between Israel and the Palestinian Authority.

Obama and Binyamin Netanyahu, the Israeli prime minister, gave brief public statements after their meeting on Wednesday. Both condemned the murder of four Israelis near Hebron on Tuesday night, which Obama called a "senseless slaughter".

"I want everybody to be clear: The United States is going to be unwavering in its support of Israel's security, and we are going to push back against these kinds of terrorist activities," Obama said.

Mahmoud Abbas, the Palestinian president, met with Obama shortly after the Netanyahu meeting. The two men allowed reporters to take photographs, but did not make any statements.

Abbas and Obama did not make any public statements following their meeting [Reuters]

Obama will also be meeting with Hosni Mubarak, the Egyptian president, and King Abdullah of Jordan. All five leaders will then gather for a dinner on Wednesday before which they are expected to deliver public statements.

Netanyahu and Abbas will meet on Thursday at the US state department for their first round of formal negotiations. Obama has set a one-year timeframe for their talks, a deadline George Mitchell, his Middle East envoy, called "realistic" in a press briefing yesterday.

"We believe these negotiations can be completed within one year," Mitchell said. "We will engage with perseverance and patience to try to bring them to a successful conclusion."

The killings in Hebron have quickly become the dominant issue in Washington. Palestinian officials have sought to shift the focus back to Israeli settlements: A 10-month moratorium on new construction in the West Bank is due to expire on September 26.

Abbas has threatened to withdraw from talks if construction resumes.

"The settlements go against the peace process. They divide the West Bank," Husam Zomlot, a spokesman for the Palestine Liberation Organisation, told Al Jazeera. "That's exactly the reason why the Palestinian negotiating team, the Palestinian president, have said that settlements can kill the peace process before it starts."

Key issues remain

Hillary Clinton, the US secretary of state, held one-on-one meetings with Netanyahu and Abbas on Tuesday aimed at "laying the groundwork" for direct talks.

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High-level talks were suspended in late 2008, when Israel invaded the Gaza Strip. And there are few illusions that new direct talks, after months of US-sponsored indirect negotiations, will overcome lingering divisions.

Huge issues remain on the table, including the status of Jerusalem, claimed by both sides as their capital, and the fate of Palestinian refugees forced from their lands.

Mark Regev, a spokesman for the Israeli prime minister, told Al Jazeera that the talks must address security challenges.

"You cannot have peace without security, the two go hand-in-hand," he said, citing a recent attack when Hamas fighters killed four Israeli settlers.

Regev acknowledged widespread "cynicism" and "scepticism" about the talks. But, he said, "it's our job, the job of leadership, to prove the sceptics wrong and to change realities to create peace."